Brooks Koepka went all-in for a win on the 18th hole at the St. Jude Invitational, and wound up with a double-bogey that cost him $455,000

• Brooks Koepka attempted to chase down Justin Thomas in the final two holes of the WGC-FedEx St. Jude Invitational on Sunday.
• After an astounding birdie on No. 17, Koepka lined up an aggressive tee shot on the final hole of the tournament hoping to force a playoff.
• Koepka wound up finding the water and went on to double-bogey the hole.
• The double-bogey moved Koepka from being alone in second behind Thomas into a four-way tie, costing him $455,000 in prize money.

Brooks Koepka went for it all as he played out the final holes of the WGC-FedEx St. Jude Invitational on Sunday, and his aggressive decision to try for the win cost him nearly half a million dollars.

After 70 of 72 holes of the tournament had been played, Koepka trailed leader Justin Thomas by two strokes. Koepka still had a chance to catch Thomas but needed to either birdie the final two holes or hope Thomas slipped up as he turned towards the clubhouse.

Nos. 17 and 18 had played as the toughest two holes at TPC Southwind all weekend, but Koepka found a miraculous, 40-foot birdie putt on the penultimate hole to give himself a puncher's chance at forcing a playoff.

Now just a stroke behind Thomas and forcing a playoff, Koepka moved to the 18th tee ready to push for a birdie. He lined up an aggressive tee shot in an attempt to cut the dog leg of the hole and give him an angle for a dart onto the green with his second shot.

Koepka's line was solid, but his drive came up just a bit shorter than it needed to and found water just off of the fairway.

After taking a penalty stroke for getting his ball wet, Koepka needed to find a way to hole out from 203 yards in order to force a playoff. To his credit, he again went for it all, sending his shot wide right of the green into a bunker. From there, Koepka would close out with a double-bogey on the hole.

Entering the 18th tee box, Koepka had been alone in second behind Thomas at 12-under for the weekend. Due to his double-bogey on No. 18, he dropped into a four-way tie for second place along with Daniel Berger, Tom Lewis, and Phil Mickelson.

The prize money for a solo-second would have sent Koepka home with $1,150,000. Instead, the four-way tie behind Thomas sent each man home with $695,000. It's still a great pay rate for four days of work, but for Koepka, his final hole cost him $455,000.

Koepka deserves all of the credit in the world for going for the win at the 18th hole — he could have played it safe, kept his ball dry, and walked away as a happy man who was a million dollars richer.

Instead, he went for it all, and while it didn't work out for him this time, Koepka's fearlessness on the course is one of the reasons he's become one of the most dominant players of his generation.

Koepka will get his next shot at the top prize this weekend when he will attempt to win his third straight PGA Championship at TPC Harding Park.

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